Xjoshua s stevens



.ers used in Fig. 7.

UNITED STATES PATENT OFFICE.

JOSHUA STEVENS, -or OHIOOPEE FALLS, MASsAoHUSETTS, ASSIGNOR TO THE J.STEVENS ARMS AND TOOL COMPANY, or SAME PLACE.

CALIPERS OR D'IVIDERS.

SPECIFICATION forming part of Letters Patent No. 377,868, dated-February14-, 1888.

Application filed SeptemberS), 1887. Serial No. 249,223. (No model.)

.Z'o all whom it may concern.-

Be it known that I, JOSHUA STEVENS, a citizen of the United States,residing in Chicopee Falls, Hampden county, Massachusetts, have inventedcertain new and useful Improvements in Calipers, Dividers,'&c.,of whichthe following is a specification.

. This invention relates to the head or hinged joint for calipers,dividers, compasses, and similar instruments. Instead of the two legsbeing interleaved at the hinge with a pintle, screw, or rivet passedthrough their respective perforated eyes, they are constructed accordingto my invention with the hinge part of each leg entirely on one side ofthe pintle and connected together through the medium of a washer or capapplied to one or both sides and having a concentric annular ribentering grooves in the hinge parts of the respective legs, wherebythelatter are retained in position and caused toturn properly around thepintle.

Figure 1 of the accompanying drawings is 'a side view showing calipersconstructed according to my invention. In dotted lines are Shown thelegs of dividers to illustrate the applicability of my inventionthereto. The remaining views are on an enlarged scale. Fig. 2 is atransverse section of the head or hinge, out along the line 2 2. Fig. 3is a fragmentary view showing the upper ends of the legs broughttogether as they are when the hinge is completed. Fig. 4 is a' plan ofthe annularly-ribbed washer. Fig. 5 is an elevation of the inner side ofone of the legs. Fig. 6 illustrates a modification, being a view likeFig. 5, with the addition of the respective annular washers to beapplied to it Shown in diametrical section. Fig. 7 is a section on theline 7 7 in Fig. 1, showing another modification; and Fig. 8 is a planof one of the wash- Let A A designate the legs of the calipers ordividers; B, the usual Spring for opening the legs; 0, the screw and Dthe nut for closing them together, and E the hinge. With the exceptionof the hinge, the constructionis the same as that heretofore known.

formed entirely on one side of a diametrical plane coincident with theaxis of the pintle a, as best shown in Fig. 3, and to enable the twolegs to be opened out to the desired angle their upper ends above thepintle are beveled back, as shown at e e in Fig. 3. In each leg isformed a nearly half round cylindrical groove, f, for the reception ofthe pintle. The legs are formed 'on one side of the head with a recess,to receive a boss, h, on the head F of the pintle, and on the other sideof the head the legs are formed with an annular groove, 0, concentricwith-the axis of the pintle, as shown in Figs. 3 and 5. The washer G,which fits against this side of the head, has a concentric annular rib,b, which enters the grooves c in the manner shown in Fig. 2, and therebyconnects together the two legs and prevents their separation or movementaway from each other, while at the same time permitting them. to turnthe one upon the other to the extent provided for by .the bevelingawayof the ends e. The head F and washer G upon opposite sides of thehead are connected together through the medium of the pintle a, which ismade in one piece with the head, and the opposite end of which passesthrough the hole in the center of the washer and is riveted downthereon. The parts being accurately fitted together, a very perfecthinge-joint is thus made, it being to the least degree possible subjectto wear and not liable to become loose. In case it wears loose to aslight extent it may be tightened again by hammering down the rivetedend of the pintle, and this is done without liability of injuring thehinge, as in the case of an interleaved hinge.

When the legs are closed together, an anguend of the pintle escrew-threaded, in order to be united to the washer Gby screwing itthereinto instead of. riveting it. In this case both the head and washershould be nicked to be engaged by a screw-driver.

While I consider it preferable to make the head F and pintle 0 both inone piece, this is not essential, as the pintle may be screwed orriveted to the head F, as well as to the washer G. Such a constructionis shown in Figs. 7 and 8, which also illustrate a modification whereinthe grooves c c in the respective legs become mere annular rabbetsaround the exterior of the head and the ribs b on the washers arearranged at the periphery thereof, so that the washers constitute, infact,caps which partially inclose the ends of the legs on opposite sidesof the head; or, in other words, it may be said that in thismodification the elements are reversed, in that an annular groove(lettered i in Fig. 8) is formed in the washer and annular ribs orprojections (lettered j j in Fig. 7) are formed on the legs and fit intothese grooves.

The pintle preferably fills the eye formed by the halfround grooves inthe respective legs, as in Fig. 2; but this is not essential, as thepintle may be made smaller than these grooves, as shown in Fig. 7.

I claim as myinvention thefollowing defined novel features orcombinations, substantially as hereinbefore specified, namely:

1. Dividers or calipers the upper ends or the legs of which are formedentirely on opposite sides of a plane coincident with thehingeaxis, andhinged together by means of washers on opposite sides of the head,andinterfitting concentric annular ribs and grooves formed on the legsand on one or both of said washers, respectively.

2. Dividers or calipers the upper ends of theflegs of which are formedentirely on opposite sides of a plane coincident with the hingeaxis,combined with a pintle passing between them, and heads or washers onopposite sides united by said pintle and constructed with in terfittingconcentric annular ribs and grooves formed on the legs and on one orboth of said washers, respectively.

3. Dividers or calipers the upper ends of the legs of which are formedentirely on opposite sides of aplanecoineident with the hingeaxis, andhaving grooves a concentric with said axis, in combination with a washerhaving an annular rib, b, entering said grooves, witha washer or head onthe opposite side of the legs, and a pintle passing through from sideto-side between the legs with its opposite ends fixed to the respectivewashers.

4. Dividers or calipers consisting of the combination of legs A A,formed with recess 9 on one side and concentric grooves c on the other,washer G, formed with rib b entering said groove, washer F, comingagainst the opposite side of the legs and having boss h entering saidrecess 9, and pintle a.

5. Dividers 0r calipers the upper ends of the legs of which are formedentirely on opposite sides of a plane coincident with the hingeaxis, cutaway at e e, and hinged together by means of washers on opposite sidesof the head, and interfitting concentric annular ribs and grooves formedon the legs and on one or both of said washers, respectively, andcombined with a eylindricallycurved leaf-spring arranged to inelose thehead.

In witness whereof I have hereunto signed my name in the presence of twosubscribing witnesses.

GEO. H. N ETTLETON, F. J. WVARNER.

